BOSTON—The last time anything even close to this happened, there were six teams in the NHL, and Boston Bruins coach Claude Julien was nine years from being born.

It was 1951 when Tod Sloan tied Game 5 of the Stanley Cup finals with 32 seconds left, and Bill Barilko, who would die in a plane crash that summer, scored 2:53 into overtime to win the Cup for the Toronto Maple Leafs against the Montreal Canadiens. Seven years before that, the Habs had scored two goals in the last five minutes before Toe Blake netted the winner in overtime against the Chicago Blackhawks.

Yes, that Toe Blake. The guy the Hanson brothers talk about being "Old Time Hockey" in Slap Shot. Those two times were as close as any team ever got to experiencing what the Bruins did on Monday night—less than five minutes away from staving off elimination in the Stanley Cup finals, then seeing their season end with a whimper.

At least the 1944 Blackhawks and 1951 Canadiens got to go to overtime. The Bruins gave up the tying goal to Bryan Bickell with 1:16 left, and then saw Dave Bolland net the Cup-winning goal 17 seconds later.

"It's a tough way to lose, tough way to lose a game, tough way to lose a series," said Boston captain Zdeno Chara.

About the only way tougher would be to have it happen in Game 7, to see the Cup slip out of your hands and into someone else's. But even that hasn't happened for a long time. The last time a Cup-winning goal was scored in the third period of Game 7 was 1971, by Montreal's Henri Richard in Chicago. Twice, Game 7s have gone to overtime, with the Detroit Red Wings winning in 1950 and 1954 over the New York Rangers and the Canadiens.

Maybe this is just what happens when Original Six teams play each other. After all, it was only last month, in this same building, that the Bruins scored two goals, 31 seconds apart, to turn a two-goal deficit with two minutes to go against the Maple Leafs into overtime in Game 7, and then a victory on Patrice Bergeron's goal in the extra session.

"I would put the Toronto comeback maybe a little crazier than that because we had to score four goals to win that game," said Julien, whose team trailed Game 7 in the first round 4-1 nearly midway through the third period on May 13. "But at the same time, it's one of those things where you look at who you played against, and that Chicago team I think lost seven games (in regulation) in the regular season, and you can see why."

The Blackhawks were indeed the best team in the NHL this season, the first team to do the double as regular-season and Stanley Cup champions since the Detroit Red Wings in 2008. But the Bruins played them as hard as anyone, including Detroit, which led the Western Conference semifinals three games to one before Chicago stormed back and won Game 7 in overtime—another crazy Original Six series.

All it does is add to the legacies of these storied franchises. For Detroit and Toronto, the tale is only of agony in an unlucky '13. For Chicago, it's a second Cup in four years. For Boston, it's much tougher to sort out, going from a victory story to be retold for ages to a defeat that is nearly incomprehensible unless you're the stoic goaltender.

"We did it to Toronto, so I guess we get a taste of our own medicine here. It sucks." said Tuukka Rask. "This season we were known to lose a couple of leads, even in the regular season we were up by goals and we lost the games. I guess that sums it up pretty good."

Only it doesn't. It's one thing to cough up a two-goal lead to the Canadiens in March and lose 6-5 in a shootout. It's something else entirely to put one foot on an airplane back to Chicago. and then have the Blackhawks skate the Cup around on your home ice.

"We had a Game 7 in front of us," said David Krejci, the leading scorer in the playoffs with 26 points. "It was right there. I felt we played a pretty good game, and we lost it. We just gave it to them, basically."